Osteoarthritis is the most common form of arthritis. It is a chronic degenerative joint disease that affects mostly middle-aged and older adults. Osteoarthritis causes the breakdown of joint cartilage. It can occur in any joint, but it most often affects the hands, knees, hips, or spine....more

A chondroblastoma is a rare type of noncancerous bone tumor that begins in cartilage. This is the specialized, gristly connective tissue from which most bones develop. It plays an important role in the growth process. There are many different types of cartilage in the body. Chondroblastoma most often affects the ends of the long bones, near the growth plate, in the arms at the shoulder, and in the legs at the hip and knee. It is also called Codman’s tumor....more

An enchondroma is a type of noncancerous bone tumor that begins in cartilage. An enchondroma most often affects the cartilage that lines the inside of the bones. It often affects the tiny long bones of the hands and feet. It may also affect other bones such as the femur (thighbone), humerus (upper arm bone), or tibia (one of the two lower leg bones)....more

Fibrous dysplasia is a chronic disorder in which an abnormal development of fibrous tissue causes bones to expand. Any bone can be affected. More than one bone can be affected at any one time, and, when multiple bones are affected, it is not unusual for them to all be on one side of the body. However, fibrous dysplasia does not spread from one bone to another....more

Osteogenesis imperfecta (OI) is an inherited (genetic) bone disorder that is present at birth. It is also known as brittle bone disease. A child born with OI may have soft bones that break (fracture) easily, bones that are not formed normally, and other problems. Signs and symptoms may range from mild to severe....more